Also you do not need to definitely upgrade to a ATmega2560 arduino that has over 200kb of flash rather than you can also go for ATmega1284/1280 based designs! thats half the falsh memory soit means saving money if not much but yes saving that god damn hard earned bucks! or maybe go for ATmega644 etc.
Talk with CrossRoads a respected forum senior member you should try his boards ,they are dependable and comes in green and yellow colors!